1. Field of the Invention
The present invention relates to an endoscope for performing endoscopy by inserting an insertion unit into a body cavity or the like.
2. Description of the Related Art
In recent years, endoscopes have been widely employed in the medical-application field and so forth. These endoscopes can optically observe a portion to be checked by inserting an insertion unit.
In the medical-application field, endoscopes are employed for endoscopy for inserting an insertion unit into a body cavity, and optically observing a portion to be checked such as an affected portion or the like using an illumination optical system and an observation optical system provided in the tip portion of the insertion unit.
Also, in endoscopy, biopsy is sometimes performed by inserting treatment equipment within a channel duct, excising of tissue of a portion to be checked, and retrieving the excised tissue from the body as necessary.
In the event of retrieving the excised tissue from the body, a surgeon who is a doctor sometimes employs a method for removing an endoscope insertion unit from the body along with treatment equipment. However, an operation for removing and reinserting the insertion unit sometimes takes time and effort.
Accordingly, for example, the conventional example in Japanese Unexamined Patent Application Publication No. 6-54853 has disclosed an arrangement wherein a tissue-retrieving filter is disposed between a suction connector at the side toward the operator of the endoscope and a suction pump connected with this suction connector, and the tissue which has passed through a duct by suction using the suction pump is retrieved by the filter.